Curable resin composition

ABSTRACT

This invention relates to a curable resin composition comprising (a) grafted primary amino group-containing polymer and (b) a dialkyl oxalate which excels in workability and reactivity and features prominence in resistance to chemicals, weatherability, veratility, etc.

This application is a continuation, of application Ser. No. 07/883,486,filed May 15, 1992, now abandoned which is a divisional of applicationSer. No. 615,180, filed Nov. 19, 1990, now U.S. Pat. No. 5,140,057.

1. Field of Invention

This invention relates to a curable resin composition. Moreparticularly, it relates to a curable resin composition comprising agrafted primary amino group-containing polymer and a dialkyl oxalate.

2. Description of the Prior Art

Heretofore, as curable resin compositions, the curable resincompositions comprising a polyhydric alcohol compound such as polyesterpolyol or acryl polyol and a polyisocyanate compound and the curableresin compositions comprising a polyamine compound such as polyamine orpolyamideamine and a polyepoxy compound have been used in variousapplications involving coating materials, adhesive agents,surface-treating agents, shaped articles, and foam resins.Jr-A-61-23,615(1986) discloses a Michael addition type curable resincomposition comprising a polyamine compound such as polyamine orpolyamideamine and a polyacryloyl group and U.S. Pat. No. 4,414,250discloses a curable resin composition comprising a polyamine compoundand a dialkyl oxalate.

The curable resin compositions which comprise a polyhydric alcoholcompound and a polyisocyanate compound feature prominence in reactivity,weatherability, versatility, etc. and yet entail the problem of toxicityof the isocyanate compound, the problem of basic unusableness of thecomposition in an aqueous system due to ready reactivity thereof withwater, and the problem of management of the isocyanate compound forcurbing the possible secondary reaction of the isocyanate compound withwater or moisture even when the composition is used in a solvent systemor a nonsolvent system. These problems remain yet to be solved. Thecurable resin compositions which comprise a polyamine compound and epoxyresin feature prominence in reactivity, resistance to chemicals,versatility, etc. and yet entail the problem of deficiency inweatherability, low-temperature curing property, etc. The Michaeladdition type curing resin compositions which comprises a polyaminecompound and a polyacryloyl group excel in low-temperature curableproperty, weatherability, etc. and yet entail the problem of deficiencyin resistance to chemicals, gloss, etc. The curable resin compositionswhich comprise a polyamine compound such as polyamine or polyamideamineand a dialkyl oxalate suffer from the problem of slowness of the rise ofthe molecular weight of the composition due to the reaction between anoligomer and a monomer and the attendant problem of slowness of themanifestation of stated physical properties. To eliminate the effects ofthese problems, curable resin compositions which comprise a dialkyloxalate and a polyamine compound obtained by modifying with a polyaminea copolymer between a copolymerizable acid anhydride such as maleicanhydride and other copolymerizable monomer has been proposed. Thesecurable resin compositions entail the problem of slowness of themanifestation of stated physical properties due to the failure of theacid anhydride group-containing copolymer to exhibit a sufficient risein the conversion and also the problem of slowness or imcompleteness ofthe curing reaction due to the formation of an inner salt with theresidual carboxyl group.

An object of this invention, therefore, is to provide a novel curableresin composition. Another object of the present invention is to providea novel curable resin composition which exhibits enhanced compressionshear adhesive strength as illustrated in the Examples set forth below.

Another object of this invention is to provide a curable resincomposition which is free from the problems observed, as describedabove, in the curable resin compositions comprising a polyhydric alcoholcompound and a polyisocyanate compound, the curable resin compositionscomprising a polyamine compound and epoxy resin, and the Michaeladdition type curable resin compositions comprising a polyamine compoundand a polyacryloyl group.

SUMMARY OF THE INVENTION

These objects are accomplished by a curable resin composition comprising(a) a grafted primary amino group-containing polymer and (b) a dialkyloxalate represented by the general formula I: ##STR1## wherein R¹ is alower alkyl group of 1 to 8 carbon atoms.

The curable resin composition of this invention, as clearly noted fromthe working examples cited hereinafter, defies the effects of moisture,water, etc., excels in workability and reactivity, and featuresprominence in resistance to chemicals, weatherability, versatility, etc.Owing to these characteristic qualities, this curable resin compositionfinds extensive utility in various applications involving coatingmaterials, adhesive agents, surface-treating agents, shaped articles,foam resins, etc.

EXPLANATION OF THE PREFERRED EMBODIMENT

The grafted primary amino group-containing polymers which are usableeffectively in this invention include (A) those obtained by effectingaminoalkyl modification on side-chain carboxyl group-containing polymerswith an alkylene imine and (B) those obtained by hydrolyzing theketimine moiety of a homopolymer polymerizing an unsaturated monomer(II) represented by the general formula II: ##STR2## wherein R² ishydrogen atom or a lower alkyl group of 1 to 2 carbon atoms, R³ and R⁴are independently a member selected from the class consisting of loweralkyl groups of 1 to 4 carbon atoms, and n is an integer in the range of0 to 2, or a copolymer polymerizing the unsaturated monomer (II)represented by the general formula II with an unsaturated monomercopolymerizable with the monomer (II) of the general formula IImentioned above.

To be more specific, (A) the grafted primary amino group-containingpolymer disclosed in U.S. Pat. Nos. 3,228,823, 3,467,611, and 4,104,230,and JP-A-63-56,549(1988), for example, which is produced by subjecting aside chain carboxyl group-containing polymer to aminoalkylationmodification with an alkylene imine and used in the present invention isa grafted primary amino group-containing polymer obtained bycopolymerizing a carboxyl group-containing unsaturated monomer withother copolymerizable unsaturated monomer (III) and aminoalkylatinga-carboxyl group of the resultant polymer through reaction thereof withan alkylene imine. Typical example of the copolymerizable monomer (III)is at least one member selected from the group consisting of(meth)acrylamides, N-methylol (meth)acrylamides, 2-hydroxyethyl(meth)acrylates, 2-hydroxypropyl (meth)acrylates, methyl(meth)acrylates, ethyl (meth)acrylates, n-propyl (meth)acrylates,isopropyl (meth)acrylates, n-butyl (meth)acrylates, isobutyl(meth)acrylates, t-butyl (meth)acrylates, 2-ethylhexyl (meth)acrylates,stearyl (meth)acrylates, lauryl (meth)acrylates, (meth)acrylonitriles,styrene, α-methyl styrene, vinyl acetate, vinyl propionate,(meth)acroleins, dimethylaminoethyl (meth)acrylates, diethylaminoethyl(meth)acrylates, butadiene, ethylene, and propylene. The alkylene imineswhich are usable effectively herein include alkylene imines such asethylene imine, propylene imine, and butylene imine. A N-(2-aminoalkyl)substituted alkylene imine such as N-(2-aminoethyl) aziridine,N-(2-aminopropyl) aziridine and N-(2-aminoethyl) propylene imine canalso be used, and ethylene imine and propylene imine are preferable.

(B) The product which is obtained by preparing a homopolymer ofunsaturated monomer (II) represented by the general formula II or acopolymer between a polymerizable unsaturated monomer (II) representedby the general formula II and an unsaturated monomer copolymerizablewith the aforementioned monomer (III) and hydrolyzing the ketiminemoiety of the resultant polymer is a polymer possessing a graftedprimary amino group obtained by hydrolyzing a homopolymer of such apolymerizable unsaturated monomer as an acryloxyalkyl ketimine or anacryloxyalkyloxyalkyl ketimine disclosed in U.S. Pat. Nos. 3,037,969 and3,497,485, for example, or a copolymer between such aketimine-containing polymerizable unsaturated monomer as mentioned aboveand at least one copolymerizable unsaturated monomer (m).

The number average molecular weight of the grafted primary aminogroup-containing polymers (A) and (B) is in the range of 3,000 to2,500,000, preferably 5,000 to 1,500,000.

These copolymers (A) and (B) used in the present invention are obtainedby polymerization such as solution polymerization, emulsionpolymerization and suspension polymerization. As a polymerizationinitiator, for example, peroxide such as persulfate salts, hydrogenperoxide, benzoly peroxide cumemen peroxide, azobisisobutylonitrile,etc. can be used. Further, a chain transfer agent such as t-dodecylmercaptane and the like may be used together with the above mentionedpolymerization initiator in order to obtain a desired molecular weightof the copolymer. The amount of the radical polymerization initiator tobe used is in the range of 0.05 to 10% by weight, preferably 0.1 to 8%by weight, based on the total amount of the monomers.

The dialkyl oxalate (b) to be used in this invention is a dialkyloxalate represented by the general formula I: ##STR3## wherein R¹ is onemember selected from the class consisting of lower alkyl groups of 1 to8 carbon atoms, preferably 2 to 5 carbon atoms. The dialkyl oxalateswhich answer this description include dimethyl oxalate, diethyl oxalate,dipropyl oxalate, di-iso-propyl oxalate, di-n-butyl oxalate,di-iso-butyl oxalate, and di-ethylhexyl oxalate, for example. ##STR4##

For the characteristic physical properties of the cured product of thecurable resin composition of this invention to be manifested, it istheoretically necessary as clearly noted from the mechanism of curingshown above that one molecule of the dialkyl oxalate represented by thegeneral formula I should undergo exchange reaction with two primaryamino groups so as to induce the curing with an amide bond. Thecomponents of the composition of this invention can be used in a molarratio indicated below, based on the theoretical curable defined above.

The molar ratio, (Number of mols of the component of general formulaI)/(Number of mols of the primary amino group), is in the range of 0.1to 2.0, preferably 0.2 to 1.0.

The reaction of curing is carried out at a temperature in the range of4° to 250° C., preferably 10° to 200° C.

Now, the present invention will be described specifically below withreference to working examples. It should be noted, however, that thisinvention is not limited in any sense to these examples.

The term "part" used in the examples refers to "part by weight" and theterm "%" to "% by weight."

REFERENTIAL EXAMPLE 1

In a flask having an inner volume of 1 liter and provided with astirrer, a reflux condenser, a thermometer, a nitrogen inlet tube, and adropping funnel, 336 parts of isopranol and 224 parts of toluene wereplaced and, under continued introduction of nitrogen gas, heated to 80°C. A polymerizable monomer mixture comprising of 72 parts of methacrylicacid, 120 parts of butyl acrylate, 48 parts of styrene, and 9.6 parts ofazobisisobutylonitrile was added dropwise thereto over a period of twohours. After the addition, the resultant mixture was left aging at 80°C. for six hours and then cooled. Consequently, there was obtained anacrylic copolymer having an involatile content of 30%. Then, thiscopolymer and 36 parts of ethylene imine added thereto at 25° C. werestirred for one hour, heated to 75° C., and left reacting at thistemperature for five hours. After completion of this reaction, the flaskwas fitted with a distiller. The reaction solution in the flask washeated under a vacuum. The effluent from the flask was replenished withtoluene and the isopropanol was allowed to flow out of the system inconjunction with the unaltered ethylene imine. The residual ethyleneimine was thoroughly removed and then the involatile component wasadjusted to 30% with methylisobutyl ketone, to obtain a graftedamine-containing acrylic copolymer.

REFERENTIAL EXAMPLE 2

In the same flask as used in Referential Example 1, 280 parts ofisopropanol and 124.6 parts of n-butoxy ethanol were placed and, undercontinued introduction of nitrogen gas, heated to 80° C. A polymerizablemonomer mixture comprising of 80.5 parts of methacrylic acid, 63 partsof methyl methacrylate, 136.5 parts of butyl acrylate, 70 parts ofstyrene, and 9 parts of azobisisobutylonitrile was added dropwisethereto over a period of two hours. After completion of the addition,the resultant mixture was left aging at 80° C. for six hours and thencooled, to obtain a polymer having an involatile content of 46.4%. Thepolymer and 33 parts of triethyl amine added thereto were uniformlymixed. The resultant mixture and 61.6 parts of an aqueous 37% ethyleneimine solution added dropwise thereto were left reacting at 80° C. forfour hours. The resulting reaction solution was combined with 8.4 partsof triethyl amine and 75 parts of deionized water, to produce a graftedamine-containing water-soluble acrylic copolymer having an involatilecontent of 40%.

REFERENCE EXAMPLE 3

In the same flask as used in Referential Example 1, 400 parts ofdeionized water and 40 parts of an anionic surfactant (25% aqueoussolution) were placed and, under continued introduction of nitrogen gas,heated to 68° C. The resultant solution in the flask and 40 parts of apolymerizable monomer mixture comprising 48 parts of acrylic acid, 160parts of 2-ethylhexyl acrylate, and 192 parts of styrene added theretowere stirred for 15 minutes. The resultant mixture was curedpolymerizing by addition thereto of 4.6 parts of an aqueous 1.75%hydrogen peroxide solution and 4.2 parts of an aqueous 3% L-ascorbicacid solution. After elapse of 15 minutes following the start ofpolymerization, the remaining polymerizing monomer mixture was uniformlyadded dropwise thereto over a period of 90 minutes. In this while, 41parts of an aqueous 1.75% hydrogen peroxide solution and 37 parts of anaqueous 3% L-ascorbic acid solution were added dropwise into the flaskat intervals of 10 minutes until completion of the dropwise addition ofthe polymerizing mixture. After completion of the dropwise addition, theresultant mixture was left aging for one hour and then cooled.Consequently, there was obtained a polymer emulsion having an involatilecontent of 44.5%. Then, 150 parts of this polymer emulsion and 40.6parts of deionized water added thereto were uniformly mixed. The dilutedpolymer emulsion and 47.8 parts of an aqueous 10% ethylene iminesolution added thereto were left reacting at 50° C. for two hours, toobtain a grafted amine-containing acrylic copolymer emulsion having aninvolatile content of 30%.

REFERENTIAL EXAMPLE 4

In the same flask as used in Referential Example 1, 520 parts ofisopropanol was placed and, under continued introduction of nitrogengas, heated to 80° C. A polymerizable monomer mixture comprising 50parts of 2-[(1,3-dimethylbutyl)imino]ethyl methacrylate, 108 parts of2-ethylhexyl acrylate, 147 parts of styrene, and 12.2 parts ofazobisisobutylonitrile was added dropwise thereto over a period of twohours. After completion of the dropwise addition, the resultant mixturewas left aging at 80° C. for six hours and cooled. A grafted primaryamine-containing acrylic copolymer having an involatile content of 33.9%was obtained by adding 43 parts of deionized water to the aged mixture.

REFERENTIAL EXAMPLE 5

In the same flask as used in Referential Example 1, 540 parts ofisopropanol was placed and, under continued introduction of nitrogengas, heated to 80° C. A polymerizable monomer mixture comprising of 150parts of 2-[(1-methylpropyl)imino]ethyl methacrylate, 100 parts of butylacrylate, 40 parts of styrene, and 11 parts of azobisisobutylonitrilewas added dropwise thereto over a period of two hours. After completionof the dropwise addition, the resultant mixture was left aging at 80° C.for six hours and cooled. A grafted primary amine-containing acryliccopolymer having an involatile content of 27.3% was obtained by adding13.3 parts of deionized water to the aged mixture.

REFERENTIAL EXAMPLE 6

In the same flask as used in Referential Example 1, 434 parts ofisopropyl alcohol and 186 parts of butyl cellosolve were placed and,under continued introduction of nitrogen gas, heated to 80° C. Apolymerizable monomer mixture comprising 112 parts of2-[(1,3-dimethylbutyl)imino]ethyl methacrylate, 63 parts of methylmethacrylate, 136.5 parts of butyl acrylate, 70 parts of styrene, and 9parts of azobisisobutylonitrile was added dropwise thereto over a periodof two hours. After completion of the dropwise addition, the resultantmixture and 42 parts of triethyl amine added thereto were left aging at80° C. for six hours and then cooled. A grafted primary amine-containingwater-soluble acryl copolymer having an involatile content of 37% wasobtained by adding 9.6 parts of deionized water to the aged mixture.

EXAMPLE 1

One hundred (100) parts of the grafted amino group-containing acryliccopolymer obtained in Referential Example 1 as a main component and 7.6parts of diethyl oxalate was uniformly mixed. The resultant mixture wassubjected to the following test. The results are shown in Table 1.

(Test of coating for curable properties and standard for evaluation)

(1) Drying property: This property was determined by applying a sampleof the mixture in a thickness of 75 μm on a glass plate with anapplicator, measuring the dryness of the applied layer by the touch of afinger with the aid of a drying meter, type RC, at 25° C. at a RH of60%, and clocking the drying time for curable.

(2) Pencil hardness: This property was determined by preparing anapplied layer of the mixture similarly to (1) and measuring the scratchhardness of a pencil under a load of 250 g in accordance with theprocedure of Japanese Industrial Standard (JIS) K-5400 using a pencilscratch tester.

(3) Gel content: This property was determined by applying a sample ofthe mixture in a suitable amount on a plate of tetrafluoroethylene resin(Teflon), allowing the applied layer to age for seven days, thenremoving the set film from the plate, and treating the film with aSoxhlet extractor using acetone for four hours and measuring the amountof gel relative to the total amount of the film.

Separately, 100 parts of the main component mentioned above and 12 partsof titanium dioxide and a suitable amount of glass beads added theretowere mixed for mutual dispersion by the use of a paint shaker for twohours and then diluted to 700 cps. Similarly to the aforementionedmixture, the resultant diluted solution and diethyl oxalate addedthereto were uniformly mixed to obtain a coating composition. Thiscomposition was subjected to the following test. The results are shownin Table 1.

(Test of film for performance and standard of evaluation) (4)Weatherability: This property was determined by applying a sample of thecomposition in a thickness of 75 μm on a stainless steel plate with anapplicator, allowing the applied layer of the composition to age at 25 Cat a RH of 60% for seven days, then exposing this layer to the radiationin a sunshing type weather-o-meter for 240 hours in accordance with theprocedure of JIS K-5400, and visually examining the layer as to thecondition of film.

(Resistance to change color)

⊚; Absence of change

∘; Sparing change of color

Δ; Slight change of color

×; Appreciable change of color

(Gloss retaining ratio)

Ratio of the gloss measured at time of test to the initial gloss.

(5) Resistance to solvent: This property was determined by preparing anapplied layer of the composition similarly to (4), rubbing this layerwith a cloth wetted with methylethyl ketone, and taking count of therubbings until the film degenerated.

EXAMPLES 2-8

Mixtures and compositions shown in Table 2 were obtained by a similarmethod of Example 1 using grafted primary amino group-containingcopolymers obtained in Referential Examples 1-6. These compositions weretested by following the procedure of Example 1. The results are shown inTable 1.

Control 1

A mixture and a coating composition were prepared by following theprocedure of Example 1, except that 19.9 parts of bis-phenol A typediglycidyl ether (epoxy compound produced by Yuka-Shell K. K. andmarketed under trademark designation of "Epikote 828") was added insteadto 100 parts of the grafted amine-containing acryl copolymer obtained inReferential Example 1. These mixture and coating composition were testedin the same manner as in Example 1. The results are shown in Table 1.

Control 2

A mixture and a coating composition were prepared by following theprocedure of Example 1, except that 19.9 parts of bis-phenol A typediglycidyl ether (epoxy compound produced by Yuka-Shell K. K. andmarketed under trademark designation of "Epikote 828") was added insteadto 100 parts of the grafted primary amine-containing acryl copolymerobtained in Referential Example 5. The mixture and the coatingcomposition were tested in the same manner as in Example 1. The resultsare shown in Table 1.

Control 3

One hundred (100) parts of a commercially available polyamideamine as amain component and 122 parts of Epikote 828 added thereto were uniformlymixed. This mixture was tested in the same manner as in Example 1. Theresults are shown in Table 1.

A coating composition was obtained by mixing 100 parts of theaforementioned main component with 18 parts of titanium dioxide and asuitable amount of glass beads and processing the resultant mixture byfollowing the procedure of Example 1. This composition was tested in thesame manner as in Example 1. The results are shown in Table 1.

Control 4

One hundred (100) parts of a commercially available acryl polyol(toluene n-butyl acetate solution having a hydroxyl group number 80 mgKOH/g solid and an involatile content of 50%) as a main component and 18parts of the trimer of 1,6-hexamethylene diisocyanate (ethyl acetatesolution having a NCO content of 16.5% and an involatile content of 75%)added thereto were uniformly mixed. The resultant mixture was dilutedwith toluene. This mixture was tested in the same manner as inExample 1. The results are shown in Table 1.

Then, 100 parts of the aforementioned acryl polyol adjusted with tolueneto an involatile content of 40% and 30 parts of titanium dioxide and asuitable amount of glass beads added thereto were mixed by following theprocedure of Example 1. A coating composition was obtained by uniformlymixing the resultant mixture with 9.6 parts of the trimer of1,6-hexamethylene diisocyanate (ethyl acetate solution having a NCOcontent of 16.5% and an involatile content of 75%). This composition wastested in the same manner as in Example 1. The results are shown inTable 1.

                  TABLE 1                                                         ______________________________________                                               Example                                                                         1      2      3    4    5    6    7    8                             ______________________________________                                        Drying                                                                        property                                                                      (hrs)                                                                         Driness by                                                                             0.3    0.4    0.5  0.5  1.0  0.4  0.5  0.5                           touch with                                                                    fingers                                                                       Driness for                                                                             6     6.5     2    8   8.5   7    7   8.5                           setting                                                                       Pencil   2H     H      F    H    H    2H   H    H                             hardness                                                                      Gel content                                                                            93     92     94   90   90   93   92   91                            (%)                                                                           Weather-                                                                      ability                                                                       Glass    97     94     90   96   97   95   94   94                            retaining                                                                     ratio (%)                                                                     Color    ⊚                                                                     ⊚                                                                     ⊚                                                                   ⊚                                                                   ⊚                                                                   ⊚                                                                   ⊚                                                                   ⊚              difference                                                                    Resistance to                                                                          108    110    102  98   97   107  102  100                           solvent                                                                       (number of                                                                    rubbings)                                                                     ______________________________________                                                           Control                                                                         1      2      3    4                                     ______________________________________                                        Drying property (hrs)                                                         Driness by touch     0.4    0.5    1.5  1.5                                   with fingers                                                                  Driness for setting   8     8.5     3   10                                    Pencil hardness      H      H      HB   H                                     Gel content (%)      90     90     82   93                                    Weatherability                                                                Glass retaining      60     68     50   96                                    ratio (%)                                                                     Color difference     Δ                                                                              Δ                                                                              X    ⊚                      Resistance to solvent (number of                                                                   95     97     20   97                                    rubbings)                                                                     ______________________________________                                    

                                      TABLE 2                                     __________________________________________________________________________                  Example                                                                       2     3     4     6     6     7     8                           __________________________________________________________________________    Coating composition                                                           Mixture                                                                       Main agent (grafted amino                                                                   Referential                                                                         Referential                                                                         Referential                                                                         Referential                                                                         Referential                                                                         Referential                                                                         Referential                 group-containing copolymer)                                                                 Example                                                                             Example                                                                             Example                                                                             Example                                                                             Example                                                                             Example                                                                             Example                     (parts)        2     3     1     4     5     6     5                                        100   100   100   100   100   100   100                         Diethyl oxalate                                                                             4.4   3.7         1.4   7.8   4.1                               Dibutyl oxalate           10.6                    10.8                        Titanium dioxide                                                                             16    12    12    14    11    15    14                         __________________________________________________________________________

EXAMPLE 9

An adhesive agent was obtained by uniformly mixing 100 parts of thegrafted primary amino group-containing acrylic copolymer emulsionobtained in Referential Example 3 with 3.7 parts of diethyl oxalate and18 parts of a 15% aqueous solution of partially saponified polyvinylalcohol whose 4% aqueous solution exhibited a viscosity of 56 cps at 25°C. This adhesive agent was applied to the opposed surfaces of two piecesof birch at a rate of 150 g/cm². The two pieces were applied to eachother across the deposited layers of the adhesive agent and then joinedfast at 25° C. under a squeezing pressure of 10 kg/cm² for one hour. Thejoined layers of the adhesive agent were left aging at 25° C. and 60% RHfor three days and then tested for normal state adhesive strength and,after repeated boiling, tested for boil-resisting adhesive strength interms of compression shear adhesive strength (kg.f/cm²) in accordancewith JIS K-6852. The results are shown in Table 3.

EXAMPLE 10

In Example 9, a coating composition without using the partiallysaponified polyvinyl alcohol and was subjected to test. The result isshown in Table 3.

Control 5

An adhesive agent was obtained by adding polyvinyl alcohol similarly toExample 9 to 100 parts of the grafted amine-containing acrylic copolymeremulsion obtained in Referential Example 3, further adding thereto 5.8parts of ethylene glycol diglycidyl ether, and uniformly mixing them.

This adhesive agent was used and tested by following the procedure ofExample 9. The results are shown in Table 3.

Control 6

A two-component type aqueous vinyl urethane type adhesive agentexhibiting an involatile component of 46.8% after preparation was usedand tested by following the procedure of Example 9. The results areshown in Table 3.

                  TABLE 3                                                         ______________________________________                                                    Compression shear adhesive strength                                      Pot life                                                                             Normal state                                                                              After repeated boiling                                     (hrs)  (kg · f/cm.sup.2)                                                                (kg · f/cm.sup.2)                          ______________________________________                                        Example 9                                                                              6<       113         65                                              Example 10                                                                             6<       104         71                                              Control 5                                                                              6<       102         55                                              Control 6                                                                              1>       100         57                                              ______________________________________                                    

In Control 6, the adhesive agent began to increase viscosity and foamvigorously after 30 minutes and became unusable after 50 minutes,respectively following the time of preparation.

What is claimed is:
 1. An adhesive agent resin composition comprising a dialkyl oxalate, and a grafted primary amino group-containing polymer obtained by amino-alkylating a carboxyl group-containing polymer with an ethylene imine or a propylene imine, said oxalate being represented by the formula I: ##STR5## wherein R^(l) is a lower alkyl group of 1 to 5 carbon atoms.
 2. The adhesive agent resin composition of claim 1 wherein said grafted primary amino group-containing polymer is obtained by copolymerizing a carboxyl group-containing unsaturated monomer with another copolymerizable unsaturated monomer (III) and aminoalkylating a carboxyl group of the resultant polymer through reaction thereof with an alkylene imine.
 3. The adhesive agent resin composition of claim 2, wherein said copolymerizable monomer (IV) is selected from the group consisting of (meth)acrylamides, N-methylol (meth)acrylamides, 2-hydroxyethyl (meth)acrylates, 2-hydroxypropyl (meth)acrylates, methyl (meth)acrylates, ethyl (meth)acrylates, n-propyl (meth)acrylates, isopropyl (meth)acrylates, n-butyl (meth)acrylates, isobutyl (meth)acrylates, t-butyl (meth)acrylates, 2-ethylhexyl (meth)acrylates, stearyl (meth)acrylates, lauryl (meth)acrylates, (meth)acrylonitriles, styrene, α-methyl styrene, vinyl acetate, vinyl propionate, (meth)acroleins, dimethylaminoethyl (meth)acrylates, diethylaminoethyl (meth)acrylates, butadiene, ethylene, and propylene.
 4. The adhesive agent resin composition of claim 1, wherein the molar ratio of said dialkyl oxalate represented by the formula I to the amino group of said grafted primary amino group-containing polymer ranges from 0.1 to 2.0.
 5. An adhesive agent resin composition comprising a dialkyl oxalate, and a grafted primary amino group-containing polymer obtained by amino-alkylating a carboxyl group-containing polymer with an alkylene imine or a propylene imine, said oxylate being represented by the formula I: ##STR6## wherein R¹ is a lower alkyl group of 1 to 5 carbon atoms said composition having a boil-resisting compression shear adhesive strength of at least 65 kg.f/cm² . 